From 56bd9678ef553498274f1d29ebb2839f220bce6d Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Cl=C3=A9ment=20Chigot?= Date: Wed, 31 Jan 2024 09:50:46 +0100 Subject: hw/sparc/leon3: check cpu_id in the tiny bootloader MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Now that SMP is possible, the asr17 must be checked in the little boot code or the secondary CPU will reinitialize the Timer and the Uart. Co-developed-by: Frederic Konrad Signed-off-by: Clément Chigot Reviewed-by: Philippe Mathieu-Daudé Message-ID: <20240131085047.18458-9-chigot@adacore.com> Signed-off-by: Philippe Mathieu-Daudé --- hw/sparc/leon3.c | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) (limited to 'hw') diff --git a/hw/sparc/leon3.c b/hw/sparc/leon3.c index 1637900162..bea84f3ad6 100644 --- a/hw/sparc/leon3.c +++ b/hw/sparc/leon3.c @@ -99,12 +99,26 @@ static uint32_t *gen_store_u32(uint32_t *code, hwaddr addr, uint32_t val) /* * When loading a kernel in RAM the machine is expected to be in a different - * state (eg: initialized by the bootloader). This little code reproduces - * this behavior. + * state (eg: initialized by the bootloader). This little code reproduces + * this behavior. Also this code can be executed by the secondary cpus as + * well since it looks at the %asr17 register before doing any + * initialization, it allows to use the same reset address for all the + * cpus. */ static void write_bootloader(void *ptr, hwaddr kernel_addr) { uint32_t *p = ptr; + uint32_t *sec_cpu_branch_p = NULL; + + /* If we are running on a secondary CPU, jump directly to the kernel. */ + + stl_p(p++, 0x85444000); /* rd %asr17, %g2 */ + stl_p(p++, 0x8530a01c); /* srl %g2, 0x1c, %g2 */ + stl_p(p++, 0x80908000); /* tst %g2 */ + /* Filled below. */ + sec_cpu_branch_p = p; + stl_p(p++, 0x0BADC0DE); /* bne xxx */ + stl_p(p++, 0x01000000); /* nop */ /* Initialize the UARTs */ /* *UART_CONTROL = UART_RECEIVE_ENABLE | UART_TRANSMIT_ENABLE; */ @@ -118,6 +132,10 @@ static void write_bootloader(void *ptr, hwaddr kernel_addr) /* *GPTIMER0_CONFIG = GPTIMER_ENABLE | GPTIMER_RESTART; */ p = gen_store_u32(p, 0x80000318, 3); + /* Now, the relative branch above can be computed. */ + stl_p(sec_cpu_branch_p, 0x12800000 + + (p - sec_cpu_branch_p)); + /* JUMP to the entry point */ stl_p(p++, 0x82100000); /* mov %g0, %g1 */ stl_p(p++, 0x03000000 + extract32(kernel_addr, 10, 22)); -- cgit v1.2.3